Bridgemarsh Island

It was surrounded by a seawall, built in 1736, and was reached from lower Althorne by a causeway over Althorne Creek, crossable at low tide – an option no longer available.

Rich in clay, the island hosted a brickworks and the remains of its chimney can still be seen. There was even a tramway that ran down to the water’s edge so the bricks could be loaded onto Thames barges.

Great Flood Breach

The island’s seawall was breached in the Great Flood of 1953, and the island abandoned to wildlife. It is now a bird sanctuary and a haven for saltmarsh flowers, and is owned by the Wildlife Habitat Trust.

Ever since the flood, the mud and silt from the island has been washing downstream towards Burnham, and has contributed to the slow covering of the sandy beaches and shingles that used to mark the Burnham foreshore.

Sailors often enjoy the challenge of circumnavigating the island on a spring tide (spring tides are high tides that occur over three days or so, every fortnight). Boats with a draught no more than 3’6″ can manage it with care, keeping to the snaking subaqua channel by watching the depthsounder or leading like billy-o (swinging a rope marked to indicate depth, with a lead weight on it). On a warm summer’s day, it is a truly beautiful, peaceful sail.